1. Field of the Invention
The present invention concerns a tool changer for a processing center, and more particularly to a work tool changer which can be constructed at reduced cost and which makes possible shorter work tool change out times. The work tool changer includes a two-armed gripper, which with one arm delivers the new work tool and with the other arm removes the no longer required work tool from the work spindle.
2. Description of the Related Art
In order to be able to accomplish the various processing steps on a workpiece automatically one after the other, automated work tool changers are employed in the processing centers, which retrieve the respectively required tools from a tool magazine, transport them to a work spindle, there exchange them for the no longer needed tool, and return the no longer needed tool to the tool magazine. In order to make possible a high flexibility of the work process and long automated processing times, work tool magazines with a high capacity are necessary. In order to store the work tools in a simple means securely in the magazine, work tool magazines are preferred in which the work tool is stored on its vertical axis. The work spindle of the processing center is preferably oriented horizontally in order to make possible a downwards freefall of turnings. Out of this there emerges the necessity that the work tool exchanger transports the work tools between the work tool magazine and the work spindles generally in three spatial axes (U-, V-, W-axis), and besides this tilts the work tool between the vertical position in the work tool magazine and the horizontal position in the work spindle. With known work tool changers the various movement steps are carried out independently from each other and one after the other. Accordingly, there are provided separate independent drive means for the individual transport steps. As a result the known work tool changers are expensive in their construction. This stepwise running of the individual movement steps requires in addition a longer work tool change out time.